Expansion compensating device for valve actuating mechanism



xmscmmlsux4 l July 21, 1931. J. wElNER ET AL EXPANSION COMPENSATINGDEVICE FOR VALVE ACTUATING Filed Nov. 21, 1928 @magali fil/ias lf2! f'cff- 50127116/ Z5. L/al' .oMu

Patented July 21, 17931 UNITED STATES PATENT OFFICE JU'IIIUS WEIN'ER, OFPHILADELPHIA, PENNSYLVANIA, AND SAMUEL IB. SKLAR, OF

MINNEAPOLIS, MINNESOTA EPANSION COMPENSATING DEVICE FOR VALVE AGTUATING-MECHANISM Application filed November 21, 1928.

y lOur invention relates to internal combustion engines and has for itsobject to provide a simple and highly efficient expansion compensatingdevice for valve actuating mechanism.

The aims of the invention are to hold the tappets of an internalcombustion engine in contact with the valve stems at all times therebyeliminating valve taps and to compensate for expansion under varyingtemperatures, vvhichwould change the relation of the valve stems inrespect to their actuating mechanism and prevent the valves from beingheld open to the burning thereof.

To the above end, generally stated, the invention consists of the noveldevices and combinations of devices hereinafter described and defined inthe claims.

In the accompanying drawings, which illustrate the invention, likecharacters indicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a fragmentary view of an internal combustion engine having theinvention embodied therein;

Fig. 2 is a fragmentary detail View with some parts sectioned on theline 2-2 of Fig. 1, on anenlarged scale; Y

Fig. 3 is an enlarged view of the cam and tappet, as shown in Fig. 2;

Fig. 4 is a fragmentary detail view principally in section taken on theline 4-41 of Fig. 3;

Fig. 5V is a side elevation of the shoes, as

shown in Fig. 2, removed from the cam;

and

Fig.` 64 is a view of the cam as shown in Fig. 2'with the shoes removed.

f the parts of the multiple cylinder en- 40 gine illustrated in thedrawings, it is iinportant to note the exhaust and intake "valves 7 and8, respectively, valve stem guides 9, valve springs 10, valve springseats 11, valve lifter adjusting screws 12,

y lock nuts 13, valve lifters or tappets 1-1,

cam shaft 15 and cams 16 integrally formed with said shaft. The partsthus far Vdescribed are of standard and well fknown construction.

It may be here stated that in the present said calks.4 17 have the samecontour as the cam 16 and Serial No. 320,864.

arrangement of the above described parts the tappets let rest directlyon the cams 16 and when on the low portions of said cams the valves areheld closed by the springs 10 and when on the high portions of the cams16 the valves are held open by said cams. To insure the closing of thevalves it is necessary to leave clearance between the valve lifteradjusting screws 12 and the stems of the valves. If this clearance issuch as to make the action of the tappets la very quiet the valves dueto expansion will not always close with a result of poor compression andthe accumulation of carbon on the valves which often results in theburning thereof. On the other hand, if the clearance between the valvelifter adjusting screws 12 and the stems of the valves is such as toinsure the closing of the valves under all conditions of i the enginewhether cold or hot, the tappets will be very noisy and subject toagreat deal of wear.

Referring now 1n detail to the expansion compensating device, therebeing one for each cam 16, the same includes a pair of segmental Vshoes17 hingedly connected at 1S for circumferentially expanding and con- 17are inturned calks 20 which extend into seats 2l in the end portions ofthe retaining groove 19. The outer faces of the calks 2O extend in thesame plane and whichplane is 'perpendicular to a line extending from theapex of the cam 16 through the axes of the cam shaft 15 and hingeconnection 18. Said calks 2O at their inner faces are beveled and theseats 21 have the saine general shape as The outer surfaces of the shoestheir thickness is less than that of the ret-aining groove 19.

A leaf spring 22 yieldingly holds each raised in the retaining groove 19so that its outer face extends outward thereof, as best shown in Figs. 3and 4. The springs 22 extend longitudinally in the retaining groove 19and are intermediate'ly secured by a pair of circumferentially spacedscrews 23 to the cam 16.

The ends of the springs 22 are shaped to form small substantially roundopen secondarysprings 124. r@Fliese secondary springs 241- are removablymounted in open segmental seats 25 in the bottoms olf the Ashoes 17.Said seats 25 .are slightly more than semi- .circles so that it lisnecessary to contract the secondary springs 24 to force the same intosaid seats or remove the same therefrom. The tension Aof the springs A22Ais such vas to hold the shoes 17 radially projected outwart `of theperiphery of the low portion of the in which the tappets 14; are raisedVwith the valve lifter adjusting screws 12 in contact with the stems ofthe valves said tension is not sufficient Vto interfere with the actionof the springs A10 in holding the valves closed.

From the above description, it is evident that the springs 22 alwayshold the valve 'lifter adjusting screws v12 cin-contact with the valvestems thus eliminating valve taps and permit the shoes 17 yto yield andcompensate for expansion and wear. The retaining groove 19 holds 'theshoes 17 against `lateral movement in respect to the cam 16 and thecalks 20, by their engagement with the seats 21 hold said shoes against.circumferential movement in said groove. As vthe tappets 14 move fromthe shoes 17 onto the .high

portions of the cams 16 vto open the valves or as they move from'saidhigh .portions `of the cams 16 `onto .the shoes 17 .the springs 22 lwillpermit slight `rocking movement .of said shoes and the hinge connection18 will also permit 4independent movements to the .slices 17 inrespect.to each other.,

Incase it is necessary toreplace or repair the shoes 17 they may bereadily detached from the springs 22 and at which time said springs maybe replaced `by a new Vone if necessary.

The above described device ymay .be-.of material assistanceinrjproperlyseating valves after they have been ground by making thefollowing adjustment, to wit:

When the motor is warm press down the pushrod in Fig. 13 with thefingers and test with a filler gauge between the valve stem and pushrodallowing sufficient clearance for factory specification 1of the car.Upon releasing the device the pushrods and valve vstems will be kept inthe proper positions. rllhis device may also `be of material-assist-ance in locating sticking valves for the reason that when avalve sticks, said device will make a valve tap and thus 4,assist inlocating the trouble.

Vlhat we-cla'im is:

1. An expansion compensating device comprising a cam, said cam having agroove therein, a -pair of .shoes mounted said groove, leaf springssecured tothe cam in 'the Abottom of thev groove, Vand the end por-.tions of each spring .engaging a .shoe .and Ayieldingly holding thesame projected outwardly of the cam.

A2. The structure .defined in claim 1, said shoes each 'having aplurality of spring seats therein, and secondary springs on the ends ofsaid leaf springs and removably mounted in -said spring seats, wherebyeach shoe is detachably .connected 1to said cam.

3. The structure defined in dlaiin 1, said shoes 'having a plurality ofspring `seats therein, and secondary springs on the rends of said leafsprings and removably mounted lin said seats, said ,secondary springs'being com-pressible .during their movement into and out of said seats.

e. The combination lwith a cam .adapted to be used in an internalcombustion engi-ine and having a circumferentially extending groovetherein, of an vexpansion compensating device comprising .shoes mountedin said groove, means .for yielding-ly urging each shoe outwardly ofsaid groove, means for holding each shoe against ,circumferentialmovement relative to the cam, and Ameans for detachably connecting saidshoe to :each cam.

5. The combination Adei-ined in claim 4, .said shoes .comprising :a pairof hingedly .connected segments. j

6. A cam adapted for use in an internal combustion engine, said camcomprising a body portion and .an .apex portion, said body portion beingpro-vided .with a circumferentially .extending groove, the .endh,p0rtionsof said groove merging into a -pair of inwardly .extendingseats, shoes mounted in said groove, an inturned calk at an end of eachshoe and extending into said seats, means yieldingly holdingzeach vshoeprojected outwardly of said.grooveand means detachably connecting saidshoesftosaid body portion.

7. The combination with a cam having-an apex and a .circumferentiallyextending groove terminating short of said apex, of a pair ofcircumferentially extending shoes mounted in said grooves, a hingeconnection for said shoes diametrically opposite said apex, means forholding said shoes against relative circumferential movement withrespect to said cam, a spring urging each shoe outwardly of said groove,and means detachably connecting said shoes and cam.

8. A cam having an apex and a circumferentially extending grooveterminating short of said apex, circumferentially extending shoescoextensive with said groove and mounted therein, spring means holdingeach shoe projected outwardly of :saidV groove, and means connectingsaid shoes and cam.

9. The construction defined in claim 8, each shoe having a plurality ofseats therein, and said connecting means comprising a plurality ofsecondary springs mounted on said spring means and adapted to removablyextend into said seats.

In testimony whereof we aHiX our signatures.

JULIUS WEINER. SAMUEL B. SKLAR.

